Combined anti-friction/hydrodynamic common shaft bearing system and methods of application

Abstract

A combined anti-friction/hydrodynamic common shaft bearing system and method of using the same to prevent reduction of the theoretical life of an anti-friction bearing subjected to axial forces within the system comprising an anti-friction bearing secured to a rotating shaft. A housing carries the shaft and includes a plurality of oil passageways to provide hydrodynamic lubrication to the system. A hydrodynamic thrust bearing is secured to the housing adjacent to the anti-friction bearing, and a one thrust-collar is secured to the rotating shaft adjacent the hydrodynamic thrust bearing, with an axial gap between the thrust-collar and the hydrodynamic thrust bearing. The system inhibits axial forces on the anti-friction bearing which would otherwise cause premature failure of the bearing.

1 . An anti-friction/hydrodynamic common shaft system, comprising:
 a rotating shaft comprising an upstream portion having a first end, a downstream portion having a second end, and an input/output section therebetween;   at least one anti-friction bearing secured to the rotating shaft upstream portion and/or downstream portion;   a housing carrying said rotating shaft comprising a lower housing member having a plurality of oil passageways and an upper housing member for placement on the lower housing member;   at least one hydrodynamic thrust bearing secured to the lower housing member and/or upper housing member and adjacent the at least one anti-friction bearing;   at least one thrust-collar secured to the rotating shaft and adjacent to at least one hydrodynamic thrust bearing;   an axial clearance between the at least one thrust-collar and the at least one hydrodynamic thrust bearing; and   a lubricating medium for hydrodynamic lubrication of the at least one anti-friction bearing, the at least one hydrodynamic thrust bearing, and the at least one thrust-collar via the plurality of oil passageways.   
     
     
         2 . The anti-friction/hydrodynamic common shaft system of  claim 1 , wherein the at least one anti-friction bearing, the at least one hydrodynamic thrust bearing, and the at least one thrust-collar form a bearing arrangement, and wherein the bearing arrangement prevents axial forces from inhibiting the L10 life of the at least one anti-friction bearing in the system. 
     
     
         3 . The anti-friction/hydrodynamic common shaft system of  claim 1 , wherein the lower housing member and the upper housing member comprise arcuate channels for registration of the at least one anti-friction bearing with the housing, and wherein the arcuate channels of the lower housing member include orifices for fluid communication with the plurality of oil passageways. 
     
     
         4 . The anti-friction/hydrodynamic common shaft system of  claim 1 , wherein the at least one anti-friction bearing comprises a roller bearing. 
     
     
         5 . The anti-friction/hydrodynamic common shaft system of  claim 1 , wherein the at least one hydrodynamic thrust bearing comprises a plurality of projecting portions on an interior arcuate portion of the at least one hydrodynamic thrust bearing. 
     
     
         6 . The anti-friction/hydrodynamic common shaft system of  claim 2 , wherein the at least one bearing assembly comprises a plurality of bearing assemblies, such that one of the plurality of bearing assemblies is disposed on the upstream portion and another of the plurality of bearing assemblies is disposed on the downstream portion. 
     
     
         7 . A method of preventing degradation of the theoretical L10 life of an anti-friction bearing subjected to axial forces within an anti-friction/hydrodynamic common shaft system, comprising:
 providing a housing comprising a lower housing member having a plurality of oil passageways and an upper housing member for placement on the lower housing member;   providing a rotating shaft comprising an upstream portion having a first end, a downstream portion having a second end, and an input/output section therebetween;   securing a first anti-friction bearing to the rotating shaft upstream portion or downstream portion;   placing the rotating shaft on the lower housing member;   securing a first hydrodynamic thrust bearing to the lower housing member and/or upper housing member and adjacent the first anti-friction bearing;   securing a first thrust-collar to the rotating shaft and adjacent to the first hydrodynamic thrust bearing such that the first anti-friction bearing, the first hydrodynamic thrust bearing, and the first thrust-collar form a bearing assembly having an axial gap between the first hydrodynamic thrust bearing and the first thrust-collar;   securing the upper housing member to the lower housing member to encapsulate the bearing assembly within the housing; and   providing a lubricating medium to provide hydrodynamic lubrication to the bearing assembly via the plurality of oil passageways.   
     
     
         8 . The method of  claim 7 , wherein the lower housing member and the upper housing member comprise arcuate channels for registration of the first anti-friction bearing with the housing, and wherein the arcuate channels of the lower housing member include orifices for fluid communication with the plurality of oil passageways. 
     
     
         9 . The method of  claim 7 , wherein the first anti-friction bearing comprises a roller bearing. 
     
     
         10 . The method of  claim 7 , wherein the first hydrodynamic thrust bearing comprises a plurality of projecting portions on an interior arcuate portion of the first hydrodynamic thrust bearing. 
     
     
         11 . The method of  claim 7 , further comprising:
 securing a second anti-friction bearing to the rotating shaft downstream portion or upstream portion;   securing a second hydrodynamic thrust bearing to the lower housing member and/or upper housing member and adjacent the second anti-friction bearing;   securing a second thrust-collar to the rotating shaft and adjacent to the second hydrodynamic thrust bearing such that the second anti-friction bearing, the second hydrodynamic thrust bearing, and the second thrust-collar form a second bearing assembly having an axial gap between the second hydrodynamic thrust bearing and the second thrust-collar.   
     
     
         12 . An anti-friction/hydrodynamic common shaft, comprising:
 a rotating shaft comprising an upstream portion having a first end, a downstream portion having a second end, and an input/output section therebetween;   a first anti-friction bearing secured to the rotating shaft upstream portion;   a second anti-friction bearing secured to the rotating shaft downstream portion;   a housing carrying said rotating shaft comprising a lower housing member having a plurality of oil passageways and an upper housing member for placement on the lower housing member;   a first hydrodynamic thrust bearing secured to the lower housing member and adjacent the first anti-friction bearing;   a second hydrodynamic thrust bearing secured to the lower housing member and/or upper housing member and adjacent the second anti-friction bearing;   a first thrust-collar secured to the rotating shaft and adjacent to the first hydrodynamic thrust bearing;   a second thrust-collar secured to the rotating shaft and adjacent to the second hydrodynamic thrust bearing; and   a lubricating medium for hydrodynamic lubrication of the first and second anti-friction bearings, the first and second hydrodynamic thrust bearings, and the first and second thrust-collars via the plurality of oil passageways.   
     
     
         13 . The anti-friction/hydrodynamic common shaft system of  claim 12 , wherein the first anti-friction bearing, the first hydrodynamic thrust bearing, and the first thrust-collar form a first bearing arrangement and the second anti-friction bearing, the second hydrodynamic thrust bearing, and second first thrust-collar form a second bearing arrangement, and wherein the first and second bearing arrangements prevent axial forces from inhibiting the L10 life of the first and second anti-friction bearings in the shaft system. 
     
     
         14 . The anti-friction/hydrodynamic common shaft system of  claim 12 , wherein the lower housing member and the upper housing member comprise arcuate channels for registration of the first and second anti-friction bearings with the housing, and wherein the arcuate channels of the lower housing member include orifices for fluid communication with the plurality of oil passageways. 
     
     
         15 . The anti-friction/hydrodynamic common shaft system of  claim 12 , wherein the first and second anti-friction bearings comprise roller bearings. 
     
     
         16 . The anti-friction/hydrodynamic common shaft system of  claim 12 , wherein the first and second hydrodynamic thrust bearings each comprise a plurality of projecting portions on an interior arcuate portion of each of the first and second hydrodynamic thrust bearings.